What is SQL Injection\r\nMost new web developers have heard of SQL injection attacks, but not very many know that it is fairly easy to prevent an attacker from gaining access to your data by filtering out the vulnerabilities using MySQL extensions found in PHP. An SQL injection attack occurs when […]

It is great to be able to build small utilities on top of an excellent RDBMS. Thank you MySQL. This is a small but complex utility to perform online schema change for MySQL. We call it OSC and the source is here (Code is also available at bottom).\r\n\r\nSome ALTER TABLE statements take too long form the perspective of some MySQL users. The fast index create feature for the InnoDB plugin in MySQL 5.1 makes this less of an issue but this can still take minutes to hours for a large table and for some MySQL deployments that is too long.\r\n\r\nA workaround is to perform the change on a slave first and then promote the slave to be the new master. But this requires a slave located near the master. MySQL 5.0 added support for triggers and some replication systems have been built using triggers to capture row changes. Why not use triggers for this? The openarkkit toolkit did just that with oak-online-alter-table. We have published our version of an online schema change utility (OnlineSchemaChange.php aka OSC). […]

Often we make some sketches of the database we plan to create on a blackboard or a sheet of paper before we actually design its structure on computer. After that we discuss the entities weâ€™ve got, normalize them and repeat these actions several times. As a result we get a completely approved database structure in […]

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